Introduction
Using a mobile phone while driving is dangerous. It is also against the law. However, you can use your mobile phone as a powerful music player with the help of a stereo power amplifier. This does away with the need of a sophisticated in-dash car music system.
Most mobile phones have a music player that offers a number of features including preset/manual sound equalisers. They have standard 3.5mm stereo sockets that allow music to be played through standard stereo headphones/sound amplifiers. Nokia 2700 classic is an example.
A car audio amplifier with 3.5mm socket can be designed and simply connected to the mobile phone output via a shielded cable with suitable connectors/jacks (readymade 3.5mm male-to-male connector cable is a good alternative).
Schematic
Using a mobile phone while driving is dangerous. It is also against the law. However, you can use your mobile phone as a powerful music player with the help of a stereo power amplifier. This does away with the need of a sophisticated in-dash car music system.
Most mobile phones have a music player that offers a number of features including preset/manual sound equalisers. They have standard 3.5mm stereo sockets that allow music to be played through standard stereo headphones/sound amplifiers. Nokia 2700 classic is an example.
A car audio amplifier with 3.5mm socket can be designed and simply connected to the mobile phone output via a shielded cable with suitable connectors/jacks (readymade 3.5mm male-to-male connector cable is a good alternative).
Schematic
Fig. 1: Circuit of mobile car stereo player
Fig.
1 shows the circuit of car stereo player. It is built around popular
single-chip audio power amplifier TDA1554Q (IC1). The TDA1554Q is an integrated
class-B power amplifier in a 17-lead single-in-line (SIL) plastic power
package.
The amplifier is powered from the 12V car battery through RCA socket J2. Diode D1 protects against wrong-polarity connection. LED1 indicates the power status.
Connect stereo sound signal from the 3.5mm headset socket of the mobile phone to audio input socket J1. When you play the music from your mobile, IC1 amplifies the input. The output of IC1 is fed to speakers LS1 and LS2 fitted at a suitable place in your car. Electrolytic capacitor C5 connected between pin 4 of IC1 and GND improves the supply-voltage ripple rejection. Components R2 and C4 connected at mute/standby pin (pin 14) of IC1 eliminate the switch on/off plop.
The circuit is quite compact. A good-quality heat-sink assembly is crucial for IC1.
Pin details of stereo socket and stereo jack
Fig. 2: (a) 3.5mm stereo socket and (b) 3.5mm stereo jack
Assemble the circuit on a general-purpose PCB and enclose in a suitable cabinet. Small dimensions of the power amplifier make it suitable for being enclosed in a plastic (ABS) case with vent holes. Signal input socket, speaker output terminals, on/off switch, indicator, fuse holder and power supply socket are best located on the front panel of the enclosure as shown in Fig. 3.
Cabinet Structure
Fig. 3: Proposed enclosure
What is IC TDA1554Q?
The Answer is here ->>The TDA1554Q is an integrated class-B output amplifier in a 17-lead single-in-line (SIL) plastic power package.The circuit contains 4 x 11 W single-ended or 2 x 22 W bridge amplifiers. The device is primarily developed for car radio applications.
Fig. 4: Pin diagram of IC TDA1554Q
IC TDA1554Q Features
- High output power
- Requires very few external components
- Flexibility in use - Quad single-ended or stereo BTL
- Fixed gain and Good ripple rejection
Datasheets
IC TDA1554Q
Ankur Pipara
+91- 77 37 44 84 68
